The invention relates to a method of manufacturing a semiconductor device, which method comprises providing a semiconductor body having adjacent one major surface a device region bounded by an insulating region, providing electrical connection to the device region by applying a flowable organic material to form an organic layer on the one major surface, defining a masking layer over the organic layer, etching the organic layer selectively with respect to the underlying device and insulating regions through a window in the masking layer to form an opening exposing a contact area of the device region, and depositing electrically conductive material to form a conductive pillar within the opening in contact with the contact area.
Such a method is described in EP-A-0195977. As described in EP-A-0195977, the flowable material for forming the organic layer comprises a layer of polyimide which is spun onto the one major surface thus providing a relatively flat surface. An oxide layer is provided on the polyimide layer and is followed by a photosensitive resist which is developed to form the masking layer through which the organic layer is etched using a wet or a dry etchant. Tungsten is then selectively deposited to form the conductive pillar in the opening etched in the dielectric by chemical vapor deposition using WF.sub.6 and H.sub.2. A nucleation layer may be provided in the opening to facilitate tungsten deposition by using, for example, a lift-off technique. After formation of the conductive pillar a further layer of polyimide is spun onto the surface and the above-mentioned steps repeated. Where it is desired, as shown in FIG. 8 of EP-A-0195977, to interconnect two or more pillars by a second metallization level, then a nucleation layer will normally be required to enable selective deposition of tungsten over the first polyimide layer. This process may be repeated one or more further times depending on the desired number of metallization levels. This method relies on the spun-on polyimide layers to provide the insulating or dielectric material which isolates conductive pillars from one another so that only the desired electrical connections are made. Polyimide is, however, susceptible to cracking and contamination and therefore may not provide sufficiently good insulation so that short-circuits may, for example, occur.